Note 8 - Accumulated Other Comprehensive Income (Detail) - The Balance of and Changes in Each Component of Accumulated Other Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Accumulated other comprehensive income (loss) December 31, 2012	$ 567
Net current-period other comprehensive income (loss)	(346)		56
Accumulated other comprehensive income (loss) March 31, 2013	221
Gains (Losses) Effective Hedging [Member]
Accumulated other comprehensive income (loss) December 31, 2012	(1,136)
Other comprehensive income (loss)before reclassifications	96
Amounts reclassified from other comprehensive income (loss) (1)		[1]
Net current-period other comprehensive income (loss)	96
Accumulated other comprehensive income (loss) March 31, 2013	(1,040)
Unrealized Losses OTTI [Member]
Accumulated other comprehensive income (loss) December 31, 2012	(1,017)
Other comprehensive income (loss)before reclassifications	(8)
Amounts reclassified from other comprehensive income (loss) (1)		[1]
Net current-period other comprehensive income (loss)	(8)
Accumulated other comprehensive income (loss) March 31, 2013	(1,025)
Net Unrealized Investment Gain [Member]
Accumulated other comprehensive income (loss) December 31, 2012	2,720
Other comprehensive income (loss)before reclassifications	(425)
Amounts reclassified from other comprehensive income (loss) (1)	(9)	[1]
Net current-period other comprehensive income (loss)	(434)
Accumulated other comprehensive income (loss) March 31, 2013	2,286
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated other comprehensive income (loss) December 31, 2012	567
Other comprehensive income (loss)before reclassifications	(337)
Amounts reclassified from other comprehensive income (loss) (1)	(9)	[1]
Net current-period other comprehensive income (loss)	(346)
Accumulated other comprehensive income (loss) March 31, 2013	$ 221

[1] Amounts reclassified from other comprehensive income were transferred to gain (loss) on securities, net.